table, th, td {
	border-collapse: collapse;
	border: 2px solid black;
}

th {
	color: white;
	font-weight: bold;
	background-color: blue;
}

th:hover {
	background-color: lightblue;
}

tr:nth-child(even) {
	background-color: lightgray;
}

td, th{
	padding: 10px;
}

th img {
	display: none;
	float: right;
}

.see{
	display: initial;
}

.unsee {
	display: none;
}

span {
	background-color: yellow;
}